Lee will head to Memphis, and Grizzlies guard Jerryd Bayless, a player Boston has coveted, will head to the Celtics. (Bayless arrived at the team’s hotel in Denver Monday night.) To help balance out the deal, Oklahoma City forward Ryan Gomes will return to the Celtics, who are then expected to waive him in an effort to create more financial flexibility. The Celtics will also send a 2016 second-round pick to the Thunder, who are moving Gomes to clear money off their books.

As for the remaining Celtics, they move on. They joke following practice at the Gold Crown Fieldhouse, they meet for dinner, they attempt to snap their losing skid. But change is becoming the theme of this transition season in Boston.

Just a few weeks ago, Brandon Bass and Lee were involved in trade talks that would have sent them to the Houston Rockets for Omer Asik.
Lee barely had a chance to regroup and take a couple of 3-pointers before he was shipped away for real.

Perhaps the Celtics’ younger players are stunned by the turn of events, but not the veterans, especially Gerald Wallace and Keith Bogans. They didn’t even expect to be in Boston this season.

Wallace fully expected to be fighting for a championship with Brooklyn and Bogans thought he would find a competing team to latch onto during free agency. But because their contracts fit into the blockbuster deal between the Celtics and Nets, they are graybeards in a rebuilding project.

Lee was a popular fixture in the Celtics’ locker room, although he wasn’t always happy with his playing time and role under Brad Stevens. He was a positive influence on rookie Phil Pressey and young guard Avery Bradley. He was more chipper this season because he was playing considerably better than in his first year in Boston, but Lee fully understood the Celtics were looking to move the remaining three years on his contract.

The way Wallace sees it, the younger Celtics are getting an eye-opening lesson on the business and reality of the NBA. The only consistency is change.

“We’re taking it as it comes, that’s the main thing,” Wallace said of the personnel changes. “It’s kind of difficult when you have guys that are first time being installed into the starting lineup. You ask a lot from those guys. You have a new coach, first year in the NBA, the ups and downs, the experience, he’s never been on a [losing] streak like this or a situation like this.

“It’s kind of a learning process for everybody.”

Bogans played 28 minutes in the first 33 games of the season before logging 14 in Sunday’s loss at Oklahoma City. The Celtics needed guard depth with Lee gone and MarShon Brooks in the NBADL with Maine.

He has been unhappy with his lack of playing time but understands that at 33, he was merely a piece that helped facilitate the Brooklyn trade.

Bogans is making $5 million this season. The Nets needed to include a player who could help match the salaries they were accepting from the Celtics.

Bogans could easily sit at the end of the Boston bench, munch on a sandwich, and collect his check. But he wants no part of conceding his career.

“Everybody’s advice was just to stay professional,” he said. “I’ve had people tell me, ‘Why don’t you complain?’ But that’s never been my personality to go sit in the coach’s office and complain about playing time.

“Me and Coach have had a few chats and he told me what it was and I’ll leave it at that. I’ll keep practicing, keep supporting my teammates.”

Wallace and Bogans have had to get accustomed to being afterthoughts, caught up in the grand scheme of the Celtics’ revival. And their sizable contracts make them difficult to trade.

But they have personal pride, feeling they have something left to offer in the NBA being in their early 30s. Bogans is a solid defender and career 35 percent 3-point shooter. He keeps in immaculate shape. But when Jerryd Bayless arrives, he’s likely relegated to cheerleader again.

“When you’re used to playing, it’s been tough,” Bogans said. “But I tell people, in my contract, it doesn’t say I have to play. I have to be a professional basketball player.

“I’m a competitor. I’m not one of those guys who want to take away from these young guys. I want them to be able to show what they can do, Avery Bradley, [Jordan] Crawford, all these young guys. I’ll sit back and keep my mouth shut, but that doesn’t mean I’m happy with it.”

Baxter Holmes of the Globe staff contributed; Gary Washburn can be reached at gwashburn@globe.com.